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Earth Day—which was founded in 1970 by Wisconsin Sen. Gaylord Nelson—is now a one-billion-strong global event that, for one day at least, brings awareness to the oil spills, factory pollution, and wilderness razing that threaten the environment.

Since Earth Day began as an American event, The Daily Beast wondered how green America’s cities are during the rest of the year, with data from market research firm Experian Simmons —which has tracked the greening of America for half a decade—among other sources.

To find America’s greenest cities, The Daily Beast weighed the following data: *The percentage of people who think and act in an eco-conscious way *The percentage of people who do not think and act in an eco-conscious way and may have a negative attitude toward environmental issues *The percentage of people who make a conscious effort to recycle *The number of public-transportation trips per capita for the fourth quarter of 2011, as recorded by the American Public Transportation Association *The percent of households that that use solar heating, according to the U.S. Census Bureau